Instantaneous electric water heater



June 28, 1932. J. A. c. BODENSTAB INSTANTANEOUS ELECTRIC WATER HEATER Fi led Sept. 17', 1950 2 Sheets-Sheet 1 E K 1% u M 4 Z June 1932- .1. A. c. BODENSTAB 1,364,887

INSTANTANEOUS ELECTRIC WATER HEATER Filed Sept. 17, 1930 2 Sheets-Sheet 2 I a INVENTOR pa BY flodvas'fdi CW I ATTOLW'EY Patented June 28, 1932 PATENT? OFFICE JOHN A. O. BODENBTAB, OI MICHIGAN msran'rannous morale warns rinu'rnn Application filed September 1?}1980. Serial No. 482,528.

This invention relates to water heaters.

An object of this invention is a heater under whose tank is disposed a heating element, and in whose tank and on the bottom of which I is disposed means to se regate a small quantity of water from the arger quantit in the tank, the means serving to bring sue small quantity into close proximity to the heater, and to conduct it, whenheated, to the top of .0 the tank, from where the small quantity of heated water can be withdrawn.

A further object is a tank which is com pletely surrounded by heat insulating ma? terial, such as mineral wool the insulation 15 serving to maintain the tan contents at a temperature considerably above that of unheated or "cold water.

A still further object is a heating unit for electrically heated water heaters, one which 80 is so constructed that it, and its appurtenances, may be readil removed fromthe heater proper, as a unit, without disturbing the remainder of the'heater.

Still further objects will readily occur to 35 those skilled in the art upon reference to the following description and the accompanying drawings in which Fig. 1 shows a heater of the invention, in section. L

Fig. 2 is a modified form of heater, in section.

As indicated on the drawings, there is provided a tank having a surrounding casing 12 between which and the tank is disposed an insulating packing 14, such as mineral wool. The tank is provided with a bottom 16, welded or riveted to the tank wall, and the usual cold water inlet 18 and hot water outlet 20 are provided. Disposed within the side wall of the tank and under the bottom thereof is a receptacle 24 filled with mineral wool 26 and containing a heater element 28. The latter comprises a ring of ferrous metal having electrical con-- ductors 30 and 32 secured thereto by the binding posts 34, the conductors being embedded in the wool 26 and leading to the electrical junction box 36. Connected to the latter are the conductors 38 leading to a thermostat 40 suitably mounted in the tank bottom 16 by means of the bushing 42 and supporting tube 44, the electrical connections at the box 36 bemg made by means of suitable binding posts 46, as shown. The thermostat 40 and the heater 28 are connected in series, and their 68 electrical energy is obtained from the cable or cord 48, one of whose plugs is to be plugged into a supplly line (not shown) and the other of whose p ugs 52 is adapted to be plugged into the junctionbox 36, its contacts mating with those of the box, as will be understood.

The bottom 54 of the receptacle 24 is covered with a suitable pad or plate 56 of asbestos and upon the latter are secured several thim 66 bles 58, each of the thimbles containing a coil sprin 60 into whose upper end may be inserte a yoke 62, the assembly all being embedded in the wool 26 and forming a resilient support for the heater element 28.

Means to support the heater and its component parts may be provided, and such means may be described as follows: A plurality of legs 66 support a case ring 68, the latter in turn supporting the entire heater, as shown. Projecting thru the ring 68 are sliding bolts or pins 70, each of the pins being held in place by a screw 72 threaded into the ring 68 thrua slot 7 4 in the pins, whereby the latter may be retracted from the position shown to permit the receptacle 24, normally supported thereon, to drop downward- 1y. It will be seen that when the receptacle 24 is permitted to drop, the heater element 28 is exposed and its replacement may be readily efi'ected without materially disturbing the remaining contents of the receptacle, this construction effecting considerable economies in the repair of damaged heaters.

A feature of the invention is the means by 9 which a small supply of hot water may be obtained instantaneously, even tho the tank contain a great supply of luke warm or even unheated water, and such means will now be described:

Welded or otherwise secured to the bottom 16, and in close proximity to the heating ring 28 is a metallic plate 80, roughly in the shape of an inverted saucer. The sloping surface 82 of the plate is provided with several small apertures 84 about inch below th under side oi the top central horizontal portion 86 of the plate. The last mentioned portion is apertured, there being an internal- -y threaded bushing 88 in said aperture, the bushing being integral or substantially integral with the plate. Threaded into the bufshing is a tube 90, and resting on a shoulder 92 of the bushing 88 is a second tube 94, the tube 94 surrounding the tube 90 and being joined thereto by the cap 96. Welded to each of them, the tubes 90 and 94 extending upwardly to within a short distance of the tank top 98, there being an air space 100 between the two tubes.

it will be observed that a small quantity of water coming from the inlet 18 or from the large supply within the tank 10, will go thru the apertures 84 and will be segregated from the remaining water. Such small quantity will then be heated, almost instantaneously by the heating element 28 in close proximity thereto, and will then rise in the tube 90 until it escapes at the top of the tank, the air space 100 serving to prevent such small quantity from giving up its heat to the larger quantity of water disposed within the tank.

Accordingly, it will be observed that there W has been provided a heater which can furnish a small quantity of hot water almost instantaneously, a heater whose heating element can be replaced and repaired very rapidly and easily, and one which is extremely m economical of manufacture.

In Fig. 2, the tank 102 is shown as provided with a crowned bottom 104, the concave being partially filled by a bronze casting 106 having a flat bottom against which is disposed the heater element 108, the latter being supported on the arms of a spider 110 which is in turn supported on the removable bottom 112 by the coiled spring 114, as illustrated.

A novel feature of the invention is the thermostat for the device. In the bottom 112 is disposed two receptacles 116 and 120, the former having contacts connected to the heater conductors 122, and the latter having the 59 inbent contacts 124 provided with rollers 126.

The thermostat tube 128 is fixed to the bottom 104, as shown, and is in communication with the metal bellows 130 whose lower or free end is provided with a stud 132 upon which is secured a coupling member 134, the latter receiving an elongated screw 136 which serves to clamp in place the insulating washers 138 and the insulating sleeve 140. Mounted or sweated on the latter is a copper ring 142 which serves to connect the rollers 124 when the bellows is contracted, the ring not connecting the rollers or the contacts when the bellows is expanded.

Carried on the bellows 130 is a sleeve 144 which telescopes into a second sleeve 146 secured to the bottom 112, these sleeves serving to space the thermostat parts 130-442 from the mineral wool disposed in the receptacle 148, as shown.

The conductors 122 are provided with ta ofis 150 and 152, the former being connected to one of the sockets within the receptacle by the binding screw 154 and the latter being connected to one of the contacts 124 by the screw 156. The contact 124 is connected to the other socket within the receptacle.

In this manner, when a line plug 158 is inserted into the receptacle 120, current will flow from one side of theline to the right hand contact 124, thru the copper ring (unless the bellows of the thermostat be expanded) to the other contact 124, thru the heater ring by way of tap 01f 152 108, and back to the line by way of tap o r 150 and binding post 154. If the thermostat be out of order. and the heater is to be operated without it, the line plug 158 is inserted into the receptacle 116, and no current will flow to the thermostat contacts 124, as will be clearly understood.

Now having described the invention and the preferred embodiment thereof, it is to be understood that the said invention is to be limited, not to the specific details herein set forth, but only by the scope of the claims which follow:

1. In a water heater, an insulated tank having a bottom under which is disposed a. heating element, an inverted saucer-like element on said bottom and over said heater and having apertures in its sloping wall and an opening in its top central horizontal portion, a tube leading upwardly from and in communication with the interior of said element, a tubular shield surrounding and spaced from said tube and insulating the latter, a cold water inlet leading to the bottom of the tank and a hot water outlet leading from the top of the tank.

2. In a water heater, a tank having a bottom, a receptacle under said bottom filled with a heat insulating medium, an electrically conducting ring shaped heating element resiliently supported in said receptacle and disposed under and adjacent said bottom, an electrical junction box in and on the bottom of said receptacle, and electrical conductors leading from said box to said ring element.

3. In a water heater, a tank having a bottom, a receptacle under said bottom filled with a heat insulating medium, an electrically conducting ring shaped heating element resiliently supported in said receptacle and disposed under and adjacent said bottom, an electrical junction box in and on the bottom of said receptacle, electrical conductors leading from said box to said ring element, and means supporting said receptacle and its contents in said heater.

4. In a water heater, a tank having a bottom, a receptacle under said bottom filled with a heat insulating medium, an electrically conducting ring shaped heating element resiliently supported in said rece tacle and disposed under and adjacent said ottom, an electrical junction box in and on the bottom of said receptacle, electrical conductors leading from said box to said ring element, and means supporting said receptacle and its contents in said heater, said means, when removed, permitting said receptacle and its contents to be removed from said heater as a unit.

5. In a water heater, a tank having a bottom, a receptacle under said bottom filled with a heating insulating medium, an electrically conducting ring shaped heating element supported in said receptacle and disposed under and adjacent'said bottom, an electrical junction box in and on the bottom of said receptacle, electrical conductors leading from said box to said ring element, said ring element being so supported as to be removable from said receptacle when the latter is removed from the heater, without materially disturbing the remaining contents of the receptacle.

JOHN A. C. BODENSTAB. 

